Dual booting isn't "difficult", but is frought with a lot of little issues that probably should be understood. Ex: UEFI Boot vs Legacy BIOS. Bootloaders, Grub vs Windows bootloader, etc. etc.

I prefer buying a 2nd flash drive and dual-booting across different drives entirely, so that Windows / Linux don't even share the same bootloader. Its not like $200 for another 1TB Flash drive is expensive, and apparently I need the space anyway.